The preferred embodiment concerns a method and an arrangement for setting the point (dot) size of printed images generated with the aid of an electrographic printing or copying system in which a latent raster image to be inked with toner particles is generated and is inked with toner particles to form a print image. The preferred embodiment also concerns a computer program product for implementation of the method according to the preferred embodiment, as well as a method to regulate an image generation process of an electrographic printing or copying system, and such a printing or copying system.
To achieve a desired optical appearance of a print image generated with the aid of an electrographic image generation method, it is necessary to set the point (dot) size of raster points inked with toner particles. For example, electrographic image generation methods comprise electrophotographic, magnetographic and ionographic printing methods.
In electrographic image generation methods, the point size can in particular be set via an auxiliary voltage used to ink a latent raster image, which auxiliary voltage serves as a development threshold and is designated as a bias voltage. First a latent raster image is generated on a photoconductor, said latent raster image is inked with toner particles and it is thereby developed. Such a print image is subsequently transfer-printed onto a substrate material (for example paper). A method and a device to control an image generation process of an electrographic image generation device are known from the document DE 101 36 259 A1 and the parallel U.S. Pat. No. 7,016,620 B2. A toner mark inked with toner particles is generated on the intermediate image carrier, wherein the energy with which a character generator acts to generate the toner mark is decreased relative to the energy for the generation of additional print images given otherwise identical image structure. The color density of the toner mark inked with toner particles is determined with the aid of a reflection sensor. The toner concentration in a developer station is determined with the aid of the determined color density.